The present invention relates to an insulating film-forming composition capable of forming an insulating film which has good film properties such as dielectric constant, mechanical strength and heat resistance, and which can be used in electronic devices and other applications.
Recent advances in the levels of integration, functionality and performance of semiconductor integrated circuits (IC) have led to increases in circuit resistance and capacitance between interconnects, and to increases in power consumption and delay time. Of these, because an increase in the delay time lowers the signal speed of semiconductor integrated circuits and leads to crosstalk, a lower interconnect resistance and a lower parasitic capacitance are desired in order to shorten the delay time and thus increase the speed of the semiconductor integrated circuit. One specific approach for lowering the parasitic capacitance currently being tried is to cover the periphery of the interconnects with a low-dielectric insulating film. In addition, it is desired that such an insulating film have an excellent heat resistance capable of withstanding the thin film-forming operation during mounting board production and subsequent operations such as chip connection and pin attachment, and a chemical resistance capable of withstanding wet processes. Moreover, in recent years, increasing use is being made of low-resistance copper interconnects in place of aluminum interconnects; with this transition, planarization using a chemical-mechanical polishing (CMP) process has become commonplace. A high mechanical strength capable of withstanding the CMP process is thus desired.
Silicon dioxide (SiO2, dielectric constant (k)=3.9) has hitherto been used as the insulating film to cover the periphery of interconnects. However, to achieve a lower dielectric constant in the insulating film, investigations are being conducted on the use of spin-coated dielectric films which have a film structure that is relatively easy to control and thus enable a lower dielectric constant to be readily achieved.
For example, JP 2000-191752 A and JP 2006-525413 A disclose low-dielectric constant insulating film-forming, coating materials composed primarily of polyphenylene-based organic polymers.